Patient-specific pre-operative planning

ABSTRACT

A method for pre-operative orthopedic planning includes obtaining only a high-resolution knee-joint scan of a patient, determining hip rotation center and ankle rotation center from anthropometric data based on personal data of the patient, and determining a mechanical axis of the knee joint based on the anthropometric data. The method also includes preparing at least a two-dimensional image model of the knee joint using the knee-joint scan and the determined mechanical axis, and preparing a pre-operative surgical plan based on the image of the knee joint.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation-in-part of U.S. application Ser. No.12/955,361 filed Nov. 29, 2010, which is a continuation-in-part of U.S.application Ser. Nos. 12/938,905 and 12/938,913, both filed Nov. 3,2010, and which are continuation-in-part of U.S. application Ser. No.12/893,306 filed Sep. 29, 2010, which is a continuation-in-part of U.S.application Ser. No. 12/888,005, filed Sep. 22, 2010, which is acontinuation-in-part of U.S. application Ser. No. 12/714,023, filed Feb.26, 2010, which is a continuation-in-part of U.S. application Ser. No.12/571,969, filed Oct. 1, 2009, which is a continuation-in-part of U.S.application Ser. No. 12/486,992, filed Jun. 18, 2009, and is acontinuation-in-part of U.S. application Ser. No. 12/389,901, filed Feb.20, 2009, which is a continuation-in-part of U.S. application Ser. No.12/211,407, filed Sep. 16, 2008, which is a continuation-in-part of U.S.application Ser. No. 12/039,849, filed Feb. 29, 2008, which: (1) claimsthe benefit of U.S. Provisional Application No. 60/953,620, filed onAug. 2, 2007, U.S. Provisional Application No. 60/947,813, filed on Jul.3, 2007, U.S. Provisional Application No. 60/911,297, filed on Apr. 12,2007, and U.S. Provisional Application No. 60/892,349, filed on Mar. 1,2007: (2) is a continuation-in-part U.S. application Ser. No.11/756,057, filed on May 31, 2007, which claims the benefit of U.S.Provisional Application No. 60/812,694, filed on Jun. 9, 2006; (3) is acontinuation-in-part of U.S. application Ser. No. 11/971,390, filed onJan. 9, 2008, which is a continuation-in-part of U.S. application Ser.No. 11/363,548, filed on Feb. 27, 2006; and (4) is acontinuation-in-part of U.S. application Ser. No. 12/025,414, filed onFeb. 4, 2008, which claims the benefit of U.S. Provisional ApplicationNo. 60/953,637, filed on Aug. 2, 2007.

This application is continuation-in-part of U.S. application Ser. No.12/872,663, filed on Aug. 31, 2010, which claims the benefit of U.S.Provisional Application No. 61/310,752 filed on Mar. 5, 2010.

This application is a continuation-in-part of U.S. application Ser. No.12/483,807, filed on Jun. 12, 2009, which is a continuation-in-part ofU.S. application Ser. No. 12/371,096, filed on Feb. 13, 2009, which is acontinuation-in-part of U.S. application Ser. No. 12/103,824, filed onApr. 16, 2008, which claims the benefit of U.S. Provisional ApplicationNo. 60/912,178, filed on Apr. 17, 2007.

This application is also a continuation-in-part of U.S. application Ser.No. 12/103,834, filed on Apr. 16, 2008, which claims the benefit of U.S.Provisional Application No. 60/912,178, filed on Apr. 17, 2007.

This application is also a continuation-in-part of U.S. application Ser.No. 12/255,945, filed on Oct. 22, 2008.

The disclosures of the above applications are incorporated herein byreference.

INTRODUCTION

The present teachings provide various methods of pre-operative planningfor orthopedic procedures customized for particular patients.

SUMMARY

The present teachings provide a method for pre-operative orthopedicplanning includes obtaining only a high-resolution knee-joint scan of apatient, determining hip rotation center and ankle rotation center fromanthropometric data based on personal data of the patient, anddetermining a mechanical axis of the knee joint based on theanthropometric data. The method also includes preparing at least atwo-dimensional image model of the knee joint using the knee-joint scanand the determined mechanical axis, and preparing a pre-operativesurgical plan based on the image model of the knee joint.

The present teachings provide a method for pre-operative orthopedicplanning that includes obtaining only a high-resolution knee-joint scanof a patient, taking a digital photographic image of the patient, anddetermining a hip rotation center and an ankle rotation center from thedigital photographic image. The method also includes determining amechanical axis of the knee joint from the knee-joint scan and the hipand ankle rotation centers, preparing a at least a two-dimensional imagemodel of the knee joint using the knee-joint scan and the determinedmechanical axis, and preparing a pre-operative surgical plan based onthe image model of the knee joint.

The present teachings provide a method for pre-operative orthopedicplanning that includes creating a diseased bone database, obtainingpersonal data of a patient, and selecting a best-fit bone model from thediseased bone database based on the personal data of the patient. Themethod also includes transforming the best fit model to a customizedmodel matching the personal data of the patient, and preparing apre-operative surgical plan based on the customized model withoutobtaining image data of the patient.

Further areas of applicability of the present teachings will becomeapparent from the description provided hereinafter. It should beunderstood that the description and specific examples are intended forpurposes of illustration only and are not intended to limit the scope ofthe present teachings.

BRIEF DESCRIPTION OF THE DRAWINGS

The present teachings will become more fully understood from thedetailed description and the accompanying drawings, wherein:

FIG. 1 is a flowchart of an implant manufacturing method according tothe present teachings;

FIG. 1A is a flowchart of an implant manufacturing method according tothe present teachings;

FIG. 2 is a diagram illustrating a computer interface for an implantmanufacturing method according to the present teachings;

FIG. 3 is perspective view of a generic casting of an implant accordingto the present teachings;

FIG. 4 is a posterior view of a generic casting according to the presentteachings;

FIG. 4A is a posterior view of a generic casting including a pluralityof additional modifiable features according to the present teachings;

FIG. 5 is a plan view of a generic casting according to the presentteachings;

FIG. 5A is a plan view of a generic casting including a plurality ofadditional modifiable features according to the present teachings;

FIG. 5B is a distal view of a three-dimensional image of the patient'sdistal femur showing planned resection planes according to the presentteachings;

FIG. 50 is a anterior view of a three-dimensional image of the patient'sdistal femur showing planned resection planes according to the presentteachings;

FIG. 6 is a flow chart for an osteophyte/protrusion removal controlmethod according to the present teachings;

FIG. 7 is a representative image of a patent's anatomy showingosteophyte/protrusion control tools for modifying the image;

FIGS. 8 and 9 are representative images of a patent's anatomy showingexemplary osteophyte/protrusion locations;

FIG. 10 is a representative image of a patent's anatomy showingrepresentative depth control selections for surgeon manipulation;

FIGS. 11 and 12 are representative images of a patent's anatomy afterosteophyte/protrusion removal with exemplary implants attached thereon;

FIGS. 13A and 13B illustrate a flowchart of a method of implant andguide design;

FIG. 14 is a schematic view of hardware and a user;

FIG. 15 is a plan view of a display of a device;

FIG. 16 is an exemplary illustration of a patient in preparation for aknee joint arthroplasty according to a method of the present teachings;

FIG. 17 is an anterior skeletal view of an exemplary leg of a patientillustrating anatomic and mechanical axes;

FIG. 18 is a flowchart of a method associated with FIG. 16 according tothe present teachings;

FIG. 19 is an exemplary illustration of a patient in preparation for aknee joint arthroplasty according to a method of the present teachings;

FIG. 20 is a flowchart of a method associated with FIG. 19 according tothe present teachings;

FIG. 21 is a flowchart of a method according to the present teachings.

FIG. 22A is an exemplary illustration of a best-fit diseased bone modelassociated with block 1174 of FIG. 21; and

FIG. 22B is an exemplary illustration of a transforming the best fitmodel of FIG. 21A to a patient-specific bone model associated with block1176 of FIG. 21.

DESCRIPTION OF VARIOUS ASPECTS

The following description is merely exemplary in nature and is in no wayintended to limit the present teachings, applications, or uses. Forexample, although some of the present teachings are illustrated for aknee implant, the present teachings can be used for any orthopedicimplant.

The present teachings provide a manufacturing method that integratespatient's anatomic and medical information with interactiveparticipation by a surgeon to select and manufacture an implant and,optionally, related surgical instruments, for a particular patient fromgenerally three options: a custom made implant specific to the patient,an implant that is only partially custom-made or a semi-custom implant,and a standard off-the shelf implant. Similarly, off-the-shelf,custom-made, or semi-custom-made instrumentation (e.g. alignment guides,drill guides, cutting guides or other instruments) can be selected andmanufactured, as recommended by the surgeon, for the surgical procedure.All the implant components, alignment guides, and other disposableinstruments can be included in a package provided to a surgeon for aspecific patient.

Referring to FIG. 1, an exemplary flowchart of an interactive implantmanufacturing method according to the present teachings is illustrated.The portion of the patient's anatomy related to the orthopedic procedureand the implant is characterized and detailed at 100. Thecharacterization can be performed with various imaging methods capableof obtaining a representation of the affected anatomy, including, forexample, soft and hard tissues. The tissues can include bone, bonejoints with or without cartilage, ligaments, or other soft tissue. Theimaging methods can include, for example, MRI, CT, ultrasound.radiography or X-ray, cameras and other devices. Newer methods can alsobe used, including, for example, T-ray computed tomography and T-raydiffraction tomography. T-ray is a pulsed terahertz (THz) radiation thatcan be used to image three-dimensional (3D) structures in thefar-infrared region. The THz-wave computed tomography system providessectional images of objects similar to conventional CT techniques suchas x-ray, but without the harmful effects of ionizing radiation. See,for example, Ferguson et al, T-ray Computed Tomography, Opt Lett. 2002Aug. 1; 27(15):1312-4.

The image information for the patient can be obtained at a medicalfacility or a doctor's office and can be sent to the manufacturer in anelectronic and/or digital form contained. The image information can bestored on a physical medium, such as a CD, DVD, flash memory device(e.g. memory stick, compact flash, secure digital card), or otherstorage device. The information may alternatively, or in addition, betransmitted electronically with the Internet or worldwide web usingappropriate transfer protocols. Also, electronic transmissions caninclude e-mail or other digital transmission to any appropriate type ofcomputer device, smart phone, PDA or other devices in which electronicinformation can be transmitted.

Appropriate handheld devices (used as illustrated in FIG. 13), caninclude handheld mobile device or portable communication devices, suchas the iPhone® handheld mobile device sold by Apple Inc., a corporationof California, USA; the LG Shine® handheld mobile device sold by LGCorp. a corporation of REPUBLIC OF KOREA; or the Blackberry Bold®handheld mobile device sold by Research In Motion Limited a corporationof CANADA. The handheld device can be those that are held in the palm ofa hand of a user, such as a surgeon (see FIG. 14). The surgeon can thenenter data with a stylus, keyboard, touch screen, etc. The handhelddevice can use local area networks, cell phone networks, or other datatransmission systems to communicate with a main memory and processor ofa service provider (see FIG. 14).

Appropriate handheld devices can provide access to electroniccommunication or file transfer protocols, such as internet or electronicmail, to transfer or access information files. The handheld devices canhave installed programs that can be used to manipulate the informationfiles, as discussed herein. Alternatively, or in addition thereto, thehandheld devices can access servers that process data files whilereceiving input through the handheld devices and displaying images tothe surgeon or user via the handheld device. In certain instances, thehandheld device may only be a client that does not process and edit adata file of the pre-op plan.

With continued reference to FIG. 1, at 110, the information collected at100 can be used to create a three-dimensional model or image of the boneor joint with or without associated soft tissue or related anatomy usingcommercially available computer modeling software from various vendorsor developers, such as, for example, from Materialise USA, Ann Arbor,Mich. The three-dimensional model of the patient's anatomy can be viewedon a computer display or other electronic screen and can also reproducedas a hard copy on film or other medium and viewed by direct or indirector backlight illumination. The model can be sized for viewing on anyappropriate screen size and may be cropped, rotated, etc. as selected bythe individual (e.g. the surgeon) viewing the screen.

At 120, soft tissue associated with the affected anatomy can bemodified, or removed or repaired, to restore alignment of the joint, forexample, or to remove torn or diseased tissue, or to cut or repairligaments, or to provide natural or artificial ligament grafts. Softtissue information can be optionally used as an additional designparameter or input for the implant design, at 125. For example, a customor patient-specific bearing articulation of a knee joint can be designedbased on the kinematic profile and the soft tissue/ligament informationavailable for a particular patient. Further, kinematic information forthe patient can be obtained by an actual gait analysis of the patient,and can also be obtained by computer modeling software that uses the MRIimages of the patient's joints and associated ligaments, muscle or othersoft tissue to derive kinematic analysis of the patient andcorresponding recommendations for soft tissue modification, such asreleasing a ligament, for example. Such software is commerciallyavailable from the Biomechanics Research Group, Inc., of San Clemente,Calif.

At 130, a preliminary pre-operative plan of the surgical procedure canbe prepared for surgeon or other medical user or technician review,including the planning of various bone resections, sizes and types ofimplants, and various geometric requirements including relevantdimensions, such as height, width, orientation of particular features,etc. The preliminary pre-operative surgical plan can include arecommendation of particular implants and associated instruments to beused in the surgical procedure, as discussed below. The preliminarypre-operative surgical plan can be in the form of digital images thatcan be viewed interactively using a computer modeling software, such asthe software referenced above. The preliminary pre-operative plan andany further changes or a finalized pre-operative plan can be a plandevised to obtain a healthy or as close to healthy anatomicalorientation after an operative procedure. The healthy anatomy can bebased on natural or pre-injury anatomy or mechanically correct orefficient anatomical orientation.

At 140, the preliminary pre-operative surgical plan can be submitted tothe surgeon (or other user) for review, either electronically or by landmail, and either in digital or hard copy form, as discussed above inconnection with transmitting imaging information. In particular, thesurgeon can review the resection planes shown in image of the patient'sanatomy, make changes in the location, size and orientation of theresection planes and, generally, work interactively until thepre-operative plan from 130 is surgeon-approved. Specifically, thesurgeon may approve the image of the patient's anatomy showingcorresponding resection planes. As shown in FIGS. 7 and 8, the patient'sanatomy 510, as represented in the image, can be, for example, a distalfemur with approved resection planes including medial and lateralanterior chamfer planes 513, medial and lateral anterior cut planes 511,medial and lateral posterior chamfer planes 512 and medial and lateralposterior cut planes 514. Following the surgeon's approval of theanatomy and the resection planes at 140, the surgeon is provided withthe opportunity to remove one or more osteophytes/protrusions from theimage of the patient's anatomy 510 at surgeon-selected locations anddepths at 500 (See FIG. 6). Removal of such protrusions and smootheningof the joint surface that receives the implant can parallel theintra-operative joint preparation by the surgeon and improve the actualfit of a surgeon-selected implant, whether patient-specific, semicustom, or off the shelf.

An automated osteophyte/protrusion removal control module 500 can beincorporated in the planning stage of the manufacturing methodillustrated in FIG. 1. The automated osteophyte/protrusion removalcontrol module 500 can be provided as a separate pre-operative planningmodule, as shown in FIG. 6, or it can be incorporated and/or fullyintegrated with the manufacturing method illustrated in FIG. 1.

Certain parts of the bone, including various bone bumps, protrusions,growths and osteophytes can be generally removed from thethree-dimensional reconstruction of a patient's anatomy before designinga patient-specific implant or semi-custom implant, or before selectingan off the shelf implant. The automated osteophyte/protrusion removalcontrol module can replace a time-consuming and potentially lessaccurate manual modification of the three-dimensional image to removesuch bone growths or osteophytes by an experienced image or CADtechnician. The automated osteophyte/protrusion removal control module500 can provide more accurate and faster removal of such boneirregularities, which can vary in shape, location and size from patientto patient. It will be appreciated that the osteophyte/protrusionremoval control module 500 can be used for smoothing out a bone surfaceby removing any type of bone protrusion, including bumps, irregularitiesand osteophytes. According to the present teachings, osteophytes areillustrated as exemplary, but not exclusive, candidates for complete orpartial removal.

Referring to FIG. 6, the osteophyte/protrusion removal control module500 can start 502 with an input of the three-dimensional image of thepatient's anatomy 510 including resection planes, as shown in FIGS. 7-9,after review and approval of the resection planes by the surgeon (orother user, including other professionals or technicians) at 140 ofFIG. 1. In the exemplary illustration of FIG. 7, the image of thepatient's anatomy 510 can be analyzed to identify osteophyte/protrusionlocations 530 (at 504 of FIG. 6) by determining tissue or bone overhangprotruding past outer edges 532 of the various resection planes, such asthe resection planes illustrated at 511, 513, 512 and 514 in FIGS. 7-9.If such osteophyte/protrusions 530 extend beyond the edges of theresection planes in the direction of the planned or anticipated implantlocation, the osteophyte/protrusions 530 can interfere with implantfitting.

Referring to FIGS. 6, 7 and 10, in addition to identifying the locationof osteophytes/protrusions 530, the osteophyte/protrusion removalcontrol module 500 can provide visual control for the surgeon to selectthe aggressiveness of osteophyte/protrusion removal, or the degree ofsmoothening and/or flattening of the corresponding joint anatomy.Specifically, by fine-tuning the osteophyte/protrusion locations, at 506of FIG. 6, the surgeon can control the depth of theosteophyte/protrusion removal in a continuous or discrete manner. In oneaspect, a landmark location 540 for each osteophyte/protrusion 530 canbe identified and pegged for measuring from and initiating a continuousseries of constant or variable depth contours 542 to aid the surgeon inselecting the depth of osteophyte/protrusion removal. The depth contourscan be automatically generated by the computer software that generates athree-dimensional model or image of the anatomy, such as the softwarecommercially available, for example, from Materialise USA, Ann Arbor,Mich. The landmark location 540 can be a location of lowest possibledepth in the vicinity of the identified osteophyte/protrusion, aminimum, or a valley location, as shown in FIG. 10. Although the depthcontours 542 are shown as discrete in FIG. 10, it will be appreciatedthat a continuous removal control can be provided, such that the surgeoncan exercise unlimited choices of depth contours for removal. The depthcontours 542 can represent curved smoothed-out surfaces under theoriginal osteophyte/protrusion 530 and can be exposed after an overlyingarea is shaved or peeled in the image of the patient's anatomy 510 bythe operation of graphical or visual removal tools provided on the imageof the patient's anatomy 510. The surgeon or other user can manipulatethe graphical removal tools with a user interface, such as a mouse,touch screen, joystick, slide pad, or other user interface.

Referring to FIG. 7, various visual removal tools can be provided foron-screen manipulation and control by the surgeon, at 508 of FIG. 6. Forexample, a removal tool corresponding to each edge of a resection planecan be provided and used to visually/graphically remove a portion of anosteophyte/protrusion associated with a particular edge 532. In FIG. 7,four such exemplary removal tools 520 a, 520 b, 520 c, 520 d(collectively referenced as 520) are shown, each removal tool associatedwith an edge of a resection plane, such as lateral and medial chamferplane and lateral and medial cut plane. Although the removal tools 520are illustrated as straight sliders in FIG. 7, the amount removedfollows a depth contour 542, as illustrated in FIG. 10. The removaltools 520 can include a visual indicator 525 that can provideinformation to the surgeon in the form of a number on a scale indicativeof the depth of aggressiveness of osteophyte/protrusion removal. Inanother aspect, the indicator 525 can provide visual information interms of variable color in shades gradually changing from minimum depthremoval (green, for example) to maximum depth removal (red, forexample).

After the surgeon completes the osteophyte/protrusion removal, thesurgeon can manipulate and superimpose implant images in relation to themodified patient's anatomy 510. In FIGS. 11 and 12, exemplary images ofa resected femur 510 and tibia 515 referenced relatively to a mechanicalaxis 522 are illustrated. The femur image illustrates the patient'sanatomy 510 after the osteophytes/protrusions 530 shown in FIGS. 8 and 9have been removed and a femoral component 560 is placed on the resultingsmoothed out surface that follows one of the depth contours 542 shown inFIG. 9.

Based on the preliminary pre-operative surgical plan and the patientinformation, the surgeon can make a recommendation regarding the designof the implant at 150, and any desired associated alignment guides at160. At 150, the surgeon can recommend a method of designing an implant.Specifically, the surgeon can select one of the following three options:a first option of a custom or patient-specific implant at 170 or asecond option of a semi-custom made implant at 180, or a third option ofa standard or off-the-shelf implant at 190. It will be appreciated that,based on the surgeon's recommendation at 140, the preliminarypre-operative surgical plan can be modified at 130 and then resubmittedto the surgeon for approval.

A custom-made implant is a patient-specific, one of a kind implantspecifically made for a particular patient, and consequently there is noinventory associated with such implant. Standard oroff-the-shelf-implants are available and stocked in a number of sizes,typically six or more, and a number of configurations or types,including bilateral or unilateral implants, constrained,semi-constrained, mobile, etc. Because of the variety of sizes andconfigurations that are kept in stock to be accommodate differentpatients, a large inventory of standard implants is created, and severalmolds for each type and size of implant may be used. As described belowin detail, semi-custom implants provide an intermediate solution betweencustom-made and off-the-shelf implants. Semi-custom implants reduce thesize of inventory and molds required for production, while allowing somedegree of patient-specific customization.

Custom or patient-specific implants, when approved by surgeon at 170 fora specific patient, can be manufactured for the patient by rapidprototyping methods, such as stereolithography or other similar methods,or by CNC milling, or other automated or computer-controlled machining,or by robotic methods, at 250. Manufacturing can take place at amanufacturing center or facility in situ or at remote or off-sitelocation. It will be understood that in situ manufacturing is used as ashort hand for a manufacturing site of the original equipmentmanufacturer (OEM), but can be physically located at a differentfacility of the OEM. Off-site or remote manufacturing will be understoodto refer to facilities operated by other manufacturers who arecontracted by the OEM for manufacturing all or some of the components orparts for the surgical procedure.

Off-the-shelf implants, when approved by the surgeon a 190, can bemanufactured by standard casting methods from bar stock or other stockmaterial at 200, then shaped to a final shape and size by grinding ormilling at 210, polished at 220, and then cleaned/passivated at 230.Such off-the-shelf implants can be part of an existing inventory, ormass-produced, or produced by just-in-time agile manufacturing methods.

Semi-custom implants, when approved by the surgeon at 180, can be madefrom a generic casting at 240, as described below, or by modifyingexisting standard implant designs to match various features orparameters based on the anatomy of the patient, as described inco-pending patent application entitled Patient-Modified Implant andAssociated Method, Ser. No. 12/103,834, filed on Apr. 16, 2008, thedisclosure of which is incorporated by reference herein. After thegeneric casting is modified for certain parameters of a patient, it canbe processed at aspects 210-230 to a passivated form. Patient-specificparameters can include parameters relating to the size of the implant,including height, width, various articulation parameters or angles,etc., as discussed in specific example below in reference to FIGS. 3-5.

The surgeon's review of the surgical plan at 140 may further include, at160, a request for one or more patient-specific alignment guides to beused with the implant. Patient-specific alignment guides are describedin co-pending patent application Ser. No. 11/756,057, filed on May 31,2007, Ser. No. 11/971,390, filed on Jan. 9, 2008, Ser. No. 12/025,414,filed on Feb. 4, 2008, and Ser. No. 12/039,849 filed on Feb. 29, 2008.The alignment guides can be manufactured at 260 with by rapidprototyping methods, such as stereolithography or other similar methodsor by CNC milling, or other automated or computer-controlled machiningor robotic methods, and cleaned at 270. The alignment guides, theimplants and optionally other disposable instruments can be packaged andsterilized at 280, and forwarded to the surgeon or the surgeon's medicalfacility for implantation at 290.

Referring to FIG. 2, a computer interface 400 to a computer program forthe management of the manufacturing method is illustrateddiagrammatically. An orthopedic system manager 402 can be in the form ofsoftware or other computer program associated with the originalequipment manufacturer. The orthopedic system manager 402 can beaccessible locally via dedicated computer machines or computer terminaldirectly communicated with software either by hard wire or wirelessly.The orthopedic system manager 402 can also be accessible remote remotelyvia the Internet or other remote communication portals using anyelectronic or other devices that can connect to the Internet or otherweb-based network, or other similar communication networks, includingcable, satellite and telephone-based networks.

The system manager 402 can provide access to patient file information,including lists of all current patients at 403, and surgery dates,surgeons, and approval status of the surgical plan for each patient, at404. Each patient file can include personal and medical information ofthe patient, such as, for example, weight, height, gender, age,lifestyle, pertinent medical records and medical history, as well asinformation on patient assessment that includes physical and kinematicevaluation pertaining to the orthopedic procedure at 406, and soft andhard tissue analysis at 408, including information provided at aspects120 and 125 of FIG. 1, as discussed above. Imaging center informationfor patient scans, as discussed in relation to aspects 100 and 110 ofFIG. 1, can added or modified at 410, and an imaging center for eachspecific patient can be specified at 412. Surgeon profiles, includingsurgeon preferences regarding anatomic axes alignment or implant andinstrument preferences that can be taken into account when preparing thepreliminary pre-operative plan discussed at aspect 130 of FIG. 1, can becreated and edited at 414. Information and selection of manufacturingcenters can be accessed at 416 for manufacturing the implants and oralignment guides as discussed in relation to aspects 260, 250, 240, and210-230 of FIG. 1. The preliminary pre-operative surgical plan for eachpatient can be provided at 418, as discussed above at 140 in referenceto FIG. 1, and e-mailed or otherwise communicated to the patient'ssurgeon at 420.

As discussed above at aspects 150 to 190 of FIG. 1, one implant optionincludes manufacturing semi-custom implants by generic casting.Illustrative examples of generic casting of a semi-custom femoralcomponent are shown in FIGS. 3-5. A generic casting 300 of the implantis a casting that is more specialized than ordinary bar stock, fromwhich any size of component can be made, but less specialized than theoff-the-shelf components that are available in a particular number ofsizes, typically six-to ten sizes and are finished from specificcastings of those sizes. The generic casting can be made in a size andshape that can accommodate a range of variable features for thecomponent, and at the same time can be machined to multiple sizes, suchas three or four smaller sizes. In contrast, off-the-shelf implantsrequire a mold or casting for each offered size, and a larger inventoryof available sizes for each implant component. The generic casting cangenerally include geometric features which are size/shape and/orpatient-independent or universal, and also features that are size/shapeor patient-specific, as discussed in the examples below. Moreparticularly, the generic casting can include at least one geometricfeature that will remain unchanged for any patient or universal feature,and at least one geometric feature that can be specifically customizedfor and is specific to a particular patient.

Referring to FIGS. 4 and 5, an exemplary generic casting 300 of afemoral component is illustrated. In this example, the generic casting300 can have an anterior flange 302 of medial-lateral width W, and/or aheight H and/or other geometric dimensions to accommodate multiple sizesof femoral components. For example, multiple sizes of left-sidedimplants 304 a, 304 b, and various sizes of right-sided implants 306 a,306 b can be formed by a single generic casting. Appropriate markings orindentations or score lines for cutting to size can be provided, such asheight markings 330, for example. The implant for a particular patientcan be formed from the generic casting 300 by selecting particularfeatures, such as the width W or height H, or other geometric featuresfor a particular patient and machining the generic casting 300 toprovide the size, dimension or shape, or combinations thereof for thatparticular geometric feature.

Referring to FIG. 5, the generic casting 300 does not include a patellatrack feature, but provides an area in which a custom patella track 308can be machined at a custom angle for each specific patient. The genericcasting 300 can also include additional material in the intercondylarnotch area 310 to allow for custom machining of the intercondylar notcharea 310 to accommodate various types of articulation or constraint inrelation to a tibial component, such cams or intercondylar boxes, andother contact areas for articulation with the tibial component inaccordance with a kinematic plan for the joint of the specific patient.Separate molds for posterior stabilized and cruciate retainingarticulations can be made, each mold capable of accommodating multiplesizes of the corresponding implant type. For example, the intercondylarnotch area 310 can be machined for line or area contact with thearticular surfaces of a tibial component of various degrees of flexion.Exemplary articulations are disclosed in commonly assigned U.S. Pat.Nos. 6,589,283, 6,413,279, and 6,165,223, and in co-pending U.S. patentapplication Ser. No. 10/840,765 filed on May 6, 2004, all of which areincorporated herein by reference. Various markings 332 corresponding todifferent sizes can be provided.

Referring to FIG. 3, the generic casting 300 can include at least onepatient-independent or universal feature, such as, for example,universal cement wells 312 or other universal features. Such universalfeatures can be used with any internal geometry 314, which can bemachined into the generic casting 300 to accommodate the appropriateshape and/or size for a specific patient.

Referring to FIGS. 3, 4A, 5A, 5B and 50, a semi-custom implant (304 a,304 b, 306 a, 306 b) can also be generated from a generic casting 300 bycustomizing a plurality of features based on the patient's anatomyduring the pre-operative planning stage in addition to or instead of theparameters discussed above. The generic casting 300 can include astandard, non-custom articulation surfaces for the medial and lateralcondyles and an internal bone engagement surface 300 a for engaging theresected femur and including five internal planes 511 a, 513 a, 517 a,512 a and 514 a (FIG. 3) corresponding to anterior cut plane 511′,anterior chamfer plane 513′, distal cut plane 517′, posterior chamferplane 512′ and posterior cut plane 514′ (FIGS. 5B and 50). The internalbone engagement surface 300 a and corresponding internal planes of thegeneric casting 300 can correspond to standard, i.e., non-custom, sizesfor the femoral component. By selecting a relatively large number ofparameters corresponding to the patient's anatomy, as captured in thethree-dimensional image of the corresponding joint portion of thepatient, the semi-custom implant can be made to correspond to thepatient's anatomy as closely as desired while retaining the internalgeometry corresponding to the resection planes in the sagittal view.More specifically, in an exemplary embodiment, at least nine parametersof the implant can be patient-specific, including three lengths and sixangles, as discussed below in reference to the preoperative plan for thespecific patient and the various planned resection planes.

In an exemplary embodiment of the preoperative plan, an image of thepatient's anatomy, i.e. the distal femur 510′ of the patient indicatingthe planned cut planes is illustrated in FIGS. 5B and 5C. FIG. 5Brepresents a distal view of the three-dimensional image of the distalfemur 510′, as reconstructed by MRI, CT or other scans. The plannedresections indicated on the image include medial and lateral sides of aposterior chamfer plane 512′, of a distal cut plane 517′, and of ananterior chamfer plane 513′. The most anterior point of theintercondylar notch is indicated by a tangent line at 907. FIG. 5Crepresents an anterior view of the three-dimensional image of the distalfemur 510′, and illustrates the distal cut plane 517′, anterior chamferplane 513′, and an anterior cut plane 511′. The straight edges of thevarious cut planes are indicated as follows in reference to FIG. 5C:posterior distal edge 950 is the posterior edge of the distal cut plane517′; anterior distal edge 952 is the anterior edge of distal cut plane517′; distal anterior edge 954 is the distal edge of the anterior cutplane 511′; and proximal anterior edge 956 is the proximal edge of theanterior cut plane 511′. FIG. 5B also illustrates the posterior distaledge 950, the anterior distal edge 952, and the distal anterior edge954.

A representative, but not exhaustive list of patient-specific parametersthat can be selected at the preoperative stage for incorporation intothe implant design after a particular size implant has been selected isindicated in FIGS. 4A and 5A-C.

Specifically, a central plane 800 perpendicular to the epicondylar axis801 of the distal femur 510′ can be identified through the center of andorthogonal to the medial-lateral width W of the generic casting 300. Thecentral plane 800 can be used as a reference plane for the bone cuts andthe various patient-specific parameters to be used in modeling thesemi-custom implant. The specified parameters can include, for example,three distances/lengths of the implant and six angles of the implant,each of which can be modified pre-operatively to be patient-specificsuch that they correspond to conform to the particular patient'sanatomy. It will be appreciated that a lesser or greater number ofparameters or different parameters can be use to customize and optimizethe implant for the patient. The following exemplary parameters areillustrated in FIGS. 4A and 5A-C: medial condyle width 802, lateralcondyle width 804, notch height 806, first, second and third medialangles 808, 810, 812; and first, second and third lateral angles 814,816, 818.

In particular, and referring to FIGS. 5B and 50, the medial condylewidth 802 is defined as the distance between the central plane 800 andthe farthest medial point/tangent line 902 (but not part of anosteophyte) on the posterior distal edge 950. The lateral condyle width804 is defined as distance between the central plane 800 and thefarthest lateral point/tangent 904 on the posterior distal edge 950 (butnot part of an osteophyte). The notch height 806 defined as the distancealong the central plane 800 from the posterior cut plane 514′ at edge906 to the most anterior point/tangent line 907 on the notch (but notpart of an osteophyte). The first medial angle 808 is defined as theangle between the central plane 800 and the line 908 connecting themedial-most points on the posterior distal edge 950 and the anteriordistal edge 952. The second medial angle 810 is defined as the anglebetween the central plane 800 and the line 910 connecting themedial-most points on the anterior distal edge 952 and the distalanterior edge 954. The third medial angle 812 is defined as the anglebetween the central plane 800 and the line 912 connecting themedial-most points on the distal anterior edge 954 and the proximalanterior edge 956. The first lateral angle 814 is defined as the anglebetween the central plane 800 and the line 914 connecting thelateral-most points on the posterior distal edge 950 and the anteriordistal edge 952. The second lateral angle 816 is defined as the anglebetween the central plane 800 and the line 916 connecting thelateral-most points on the anterior distal edge 952 and the distalanterior edge 954. The third lateral angle 818 defined as the anglebetween the central plane 800 and the line 918 connecting thelateral-most points on the distal anterior edge 954 and the proximalanterior edge 956.

Referring to FIG. 1A, when the above parameters 800, 802, 804, 806, 808,810, 812, 814, 816, 818 are identified in the pre-operative planningstage, an image of a semi custom implant customized with theseparameters can be displayed at 135 for review and comparison with theimage of the patient's anatomy. The values of the parameters 800, 802,804, 806, 808, 810, 812, 814, 816, 818 can be adjusted, as desired, andthe implant with the adjusted or finalized parameters can selected at137 and forwarded to the surgeon for review at 140 together with thepreoperative plan, as described above in connection with FIG. 1. Thepreoperative planning procedure can proceed as discussed above.

As discussed above, each semi-custom implant has an internal boneengagement geometry including five planes 511 a, 513 a, 517 a, 512 a and514 a corresponding to the resection planes and at least ninepatient-specific parameters, including the three lengths and six anglesdescribed above.

It will be appreciated from the above discussion that generic castingcan greatly reduce inventory, machining costs and investment in moldtooling, while at the same time accommodating sizes and geometricfeatures specific to a patient. Specifically, each implant type can beformed from a generic casting that can accommodate multiple AP sizescorresponding to medial-lateral widths, such as four sizes, for example.For implants that are available in eight sizes, generic casting canreduce inventory by a half, using two molds total for eight sizes.Further, additional reductions in inventory can be obtained by combiningright and left side implants into a single generic casting, as discussedabove in relation to FIG. 4.

The process can then be followed as illustrated in FIGS. 13A and 13B asdiscussed above in relation to FIG. 1. The blocks in FIGS. 13A and 13Bthat are illustrated with the same reference numerals as in FIG. 1, butaugmented with a prime are not discussed in further detail, but arediscussed above in FIG. 1 and include substantially similar processes.In addition to the various applications discussed above, input from asurgeon or other appropriate user can be provided with a handhelddevice, as discussed above. As illustrated in FIGS. 13A and B, ahandheld device can be used by the surgeon to review the pre-operativeplan at 140′. It will be understood, however, that the process forproviding a selected implant and tools can be similar to that discussedabove, for example, with reference to FIG. 1

With reference to FIG. 14, a schematic diagram illustrating main orexemplary hardware components for the process illustrated in FIGS. 13Aand 13B is illustrated. The pre-operative plan or preliminarypre-operative plan from block 130 and 130′ can be developed or producedby a service provider 700. The service provider 700 can own, operate,manage, or the like a main processor 702 and a main memory 704. The mainprocessor and main memory 702, 704 can be at the service provider 700,in communication with the service provider 700, or otherwise controlled,maintained, or used by the service provider 700. Further, the mainprocessor and main memory 702, 704 can be incorporated into a singleserver system. Regardless, the main processor 702 can process or executea program, such as a program to develop the pre-operative plan, acceptinputs from the surgeon, and augment or generate the final pre-operativeplan. In addition, the main processor 702 can also be used to design andoutput the implant and alignment guide in blocks 150, 150′, and 160,160′.

As discussed above, and further herein, the pre-operative plan can bedelivered or accessed by the surgeon via notification or surgeon accessin block 600′, 602′. The access or delivery of the pre-op plan can bevia an internet or worldwide web connection 706 that uses a firstcommunication method 708 from the service provider 700 and a secondcommunication method 710 to a handheld device 712. It will be understoodthat the first and second communication method 708, 710 can be wired orwireless and can both be the same. Alternatively, or in addition to aninternet connection a cell or mobile phone connection system 714, suchas a tower, cell phone, antenna, can be provided. A first communicationline 716 can transmit a communication through the mobile phoneconnection system 714. It will be understood that the service providercan communicate directly with the mobile phone connection system 714 viaconnection 716 or though an indirect connection 716′, such as aninternet connection. A second communication line 718 can be used by asurgeon 720 with the handheld device 712. Again, it will be understood,that the first and second communication system 716, 716′, and 718 can bewired or wireless and can be the same or different. In addition, anintermediate system, such as a laptop or desktop computer 722 can be incommunication with a system, such as the internet 706 via a firstcommunication system 724 and the handheld device 712 can beinterconnected with the computer 722 via a second communication system726. Again, the first and second communication system 724, 726 can bethe same or different and be wired or wireless.

With further reference to FIGS. 13A, 13B, and 14, the pre-operative planfrom block 130′ can be delivered to a surgeon or accessed by a surgeonin any appropriate manner, such as via the internet 706 or cellcommunication 714. The pre-operative plan can be the preliminarypre-operative plan as discussed above. The pre-operative plan caninclude or be saved as a data file, in the main memory 704 associatedwith the main processor 702 of the service provider 700, of anappropriate type including image data, patient data, resection areadata, etc. The pre-operative plan can be generated and stored by theservice provider 700. The service provider 700 can be any appropriateservice, such as an implant and/or guide manufacturer or specificationproducer. A specification producer can be a service that providesspecifications for an implant or guide to a manufacturer for production.

The service provider 700 can notify the surgeon 720 or user that thepreliminary pre-operative plan is ready for review in block 600′. Thenotification that the pre-operative plan is prepared can be performed inany appropriate manner. For example, an electronic mail notification canbe sent to the surgeon 720, a text message can be sent to the surgeon720, a telephone call can be made to the surgeon 720 via landline or awireless connection, as illustrated in FIG. 14. Regardless, the surgeoncan be notified that the pre-operative plan is ready for review in block600 through the use of the mobile device 712.

Once the surgeon 720 is notified that the pre-operative plan is readyfor review, the surgeon 720 can access the pre-operative plan in block602′. The surgeon can access the pre-operative plan in one or aplurality of ways in block 140′. For example, the surgeon 720 candownload the pre-operative plan to the handheld device in block 604′.Alternatively, or in addition thereto, the surgeon 720 can access themain processor/memory 702, 704 to review the pre-operative plan in themain memory 704 in block 606′ with the handheld device 712. It will befurther understood that the surgeon 720 may also access the plan withthe computer or terminal 722 by downloading the pre-operative plan datafile to the computer 722 on which appropriate software is installed toaccess the pre-operative plan. The surgeon 720 may also view a printoutof the pre-operative plan for manipulating or commenting on thepre-operative plan, or any other appropriate manner.

If the surgeon 720 downloads the file to the handheld device 712, thefile can be downloaded to the handheld device 712 using any appropriatetransfer protocol or communication system, as illustrated in FIG. 14.For example, the handheld device 712 can be connected to the computer722 through an appropriate communications cable or protocol 726, such asBluetooth®, a wireless communication protocol or a Universal Serial Bus(USB) cable. Once the file is downloaded to the handheld device 712, aprogram on the handheld device 712 can execute or read the file anddisplay images for the surgeon 720. The surgeon 720 can then review theplan in block 140′. For example, as illustrated in FIG. 7, a view of abone to be resected can be displayed along with the slider bars 520 forallowing editing or augmentation of the pre-operative plan by thesurgeon.

The view of the images, including the slider bars 520, can be augmentedfor the handheld device 712. For example, a cropped and zoomed image mayonly include a portion of the bone or region to be cut or resected forviewing by the surgeon. For example, as illustrated in FIG. 15, thehandheld device 712 can include a view screen 740 that displays an imageof the bone to be resected, but only includes a portion thereof, such asa lateral portion of a distal femur. The zoomed and cropped image caninclude fewer than all of the slide bars 520, such as only the slidebars 520′c and 520′d. The slide bars 520′c and 520′d can be illustratedand accessed by the surgeon to change data in the file for creation ofappropriate instruments and implants for the specific patient or foraugmentation of semi-custom or selection of an off-the-shelf instrumentand implant.

The surgeon 720 can access or change the pre-operative plan file usingthe slide bars 520′c and 520′d through any appropriate access ormanipulation process. For example, the screen 740 of the handheld device712 can be a touch screen. Accordingly, the surgeon 720 can touch thescreen with a finger or stylus to move the slider or marker portion 525on the slider bars 520′c and 520′d. Alternatively, or in additionthereto, a trackball or other pointer device 742 can be provided toaccess and move the slider bars 520′c and 520′d. R will be understoodthat the handheld device 712 can have any appropriate input devices,such as an external or connected input devices, that can be mapped forappropriate command inputs into the system for augmenting thepre-operative plan file. The changes, if made by the surgeon, can thenbe saved to the pre-operative plan file to generate an editedpre-operative plan file.

If the surgeon 720, after review of the pre-operative plan in block140′, finds the plan to be unacceptable in block 620′, the NO path 622′can be followed for the surgeon 720 to edit the plan in block 624′. Thesurgeon 720 can edit the plan in block 624 in any appropriate manner,such as by moving the slider bars 520′c and 520′d, or any otherappropriate slider bars. Alternatively, the surgeon 720 can edit thepre-operative plan in any appropriate manner, including those discussedabove. Moreover, the surgeon 720 can input changes into thepre-operative plan using any appropriate input portion, such as touchingthe screen 740. It will be understood, that the pre-operative plan filethat is downloaded to the handheld device 712 can then be saved with theedits as the edited pre-operative plan and transmitted to the serviceprovider 700 for appropriate edits to be re-reviewed or finalized, asdiscussed above. It will be understood, however, that the handhelddevice 712, which can include the appropriate program, can save the filein the appropriate format and transmit it back to the service provider700.

Alternatively, or in addition to downloading the pre-operative planfile, the handheld device 712 can access the pre-operative plan which isstored in the main storage 704 associated with the service provider inblock 606 and separate from the handheld device 712. If the handhelddevice 712 accesses the pre-operative plan on the main processor, memory702, 704, the handheld device 712 need only display an imagerepresenting a portion of the file on the display screen 740. That is,the pre-operative plan and any edits or processing made to thepre-operative plan can be done solely or substantially by the mainprocessor 702 that executes a program to manipulate and display thefile. The main processor 702 and the main memory 704 need not bephysically near or connected to the handheld device 712.

The handheld device 712 can be provided to display the image, such as animage of the bone for resection, for the surgeon 720. Therefore, thehandheld device 712 may not be required to process the pre-operativeplan file from the service provider 700, but only be provided to displaythe pre-operative plan file and receive and transmit input from thesurgeon 720. Accordingly, even if the pre-operative plan is accessedfrom the service provider in block 606, the slide bars 520′c and 520′dcan be displayed on the display 742 of the handheld device 712 for inputby the surgeon 720. The inputs, however, can be directly transmitted tothe main processor 702 for processing augmentation or editing of thefile. This is in addition or alternative to augmenting or editing thefile that has been downloaded to the handheld device 712 forre-transmission of the edited pre-operative plan to the service provider700.

By only or substantially accessing the pre-operative plan file from themain processor/memory 702, 704 data transmission can be minimized fromthe main memory 704 or provider 700 to the handheld device 712 of thesurgeon 720. Decreased data transmission can provide increased speed anddecreased data usage costs or bottlenecks in a system. In addition, thehandheld device 712 can be provided or include limited memory andprocessing capabilities when the pre-operative plan file is onlyaccessed with the handheld 712 and only small amounts of information aretransferred, for example, regarding slide bar location and smallerportions of an image file. Accordingly, it can be provided, that acomplete or pre-operative plan is transmitted to the handheld device712, processed completely on the handheld device 712, edited on thehandheld device 712, saved and re-transmitted back to the serviceprovider 700 or the handheld device 712 can only access thepre-operative plan file saved at the main memory 702 and transmit editsto the server.

Data transmission and processing can also be reduced by limiting orcropping the pre-operative plan data file. For example, as illustratedin FIG. 15, only a lateral and distal portion of the bone is illustratedon the display device or display screen 740 of the handheld device 712.It will be understood that an image file or image information caninclude the entire bone or other data saved in the image file.Accordingly, the image file can be cropped at the server or at theprovider and only a portion of the image file transmitted to thehandheld device 712. This can be done repeatedly for different portionsof the image data to allow for smaller file packet size or file size fortransmission to the handheld device 712. The cropping and compression ofthe data file can be done in substantially real-time by the server for asubstantially seamless viewing and manipulation by the surgeon.

Even if the surgeon 720 accesses the data file on the main memory 704,the surgeon 720 can review the pre-operative plan block 140′, asdiscussed above, and make a determination of whether the pre-operativeplan is acceptable in block 620′. As discussed above, if thepre-operative plan is not acceptable, the NO path 622′ can be followedto allow for surgeon edits in block 624′.

Further, regardless of the method of review of the pre-operative plan inblock 140′, the pre-operative plan can be determined to be acceptable inblock 620′ and follow the YES path 626′. When following the YES path626′, the implant can be designed and an alignment guide can be designedin blocks 150′ and 160′.

The various methods described above in connection with the preparation apre-operative plan may employ high resolution imaging of the patient'sjoint, as well as various other anatomic landmarks for obtaining themechanical and anatomic axes of a specific patient. In kneearthroplasty, for example, MRI or CT of the hip, knee and ankle as wellas an X-ray of the entire leg may be performed pre-operatively and usedwith an imaging protocol to prepare a detailed three-dimensional imageof the knee joint for the pre-operative plan. T-ray CT (TerahertzComputed Tomography) may also be used for quick, non-ionizing radiationscans using portable, battery operated sources of T-ray radiation. T-rayscanners, T-ray sources and related instruments are commerciallyavailable, for example, from Advanced Photonix, Inc, Ann Arbor, Mich.

Referring to FIGS. 16-22B, various methods of reconstructing thepatient's anatomy during the pre-operative plan while reducing the useof pre-operative scanning and imaging equipment are illustratedaccording to the present teachings.

In one embodiment, illustrated in reference to FIGS. 16-18, ahigh-resolution image of the knee joint only is used together withanthropometric data to prepare a three-dimensional model of the kneejoint. Anthropometric data are publicly available from many sources andcan include, among other things, lengths for body segments, density,mass and inertial properties, and centers of mass and axes of rotation.See, for example, David Winter, Biomechanics and Motor Control of HumanMovement, 4^(th) Edition, Chapter 4, Anthropometry, 2009, John Wiley &Sons, Inc. FIG. 4.1 of Winter's book provides, for example, various bodysegment lengths expressed as a fractions of body height. The Departmentof Defense maintains a collection of anthropometry resources. See forexample the website of the Defense Technical Information Center (DTIC)at “dtic.mil/dticasd/anthro.html#data”.

In another embodiment, illustrated in reference to FIGS. 16 and 19-20, ahigh-resolution image of the knee joint only is combined with a digitalphotograph of the patient's leg. A third embodiment, illustrated in theflowchart of FIG. 22, avoids pre-operative imaging of the patient forthe purpose of the pre-operative plan.

The use of anthropometric and personal data for determining a mechanicalaxis of the patient is illustrated in FIG. 17, in which a center ofrotation of the femoral joint or hip center 76, a center of rotation ofthe knee joint or knee center 75 and a center of rotation of the anklejoint or ankle center 78 are indicated. Corresponding distances betweenthese centers, such as hip height H1 (vertical distance between hipcenter 76 and knee center), hip offset D1 (horizontal distance betweenhip center 76 and knee center), tibial height H2 (vertical distancebetween ankle center 78 and knee center), and ankle offset D2(horizontal distance between ankle center 78 and knee center) can bedetermined from the height or other personal data of the particularpatient using publicly available anthropometric data. From this data, ahip angle α between the femoral anatomic axis AN of the femoral bone 72and the femoral mechanical axis FM can be determined. Similarly, atibial angle 3, i.e., an angle between the tibial mechanical axis TM ofthe tibial bone 74 and the femoral mechanical axis FM can be determined.

Referring to FIG. 16, a high resolution scan of the knee joint 70 of apatient 60 can be taken pre-operatively using an MRI scanner or CTscanner or other scanner 50. Scanning is focused on the knee joint 70 ofthe patient, as illustrated in FIG. 16. The high resolution scan of theknee joint obtained can be used for the methods illustrated in theflowcharts of FIGS. 18 and 20 as discussed below.

Referring to FIG. 18, various personal patient data are obtainedpreoperatively, at 1100. The personal patient data can includeinformation for use with anthropometric databases and can include, forexample, height, weight, body mass index (BMI), age, gender, race,ethnicity, daily activity, disability, etc. A high resolution scan ofthe knee joint 70 of the patient is also obtained pre-operatively at1102, as illustrated in FIG. 16. Using the public anthropometric data,the hip height H1, the hip angle α, the tibial height H2 and tibialankle 13 can be determined, at 1104 using the personal patient data.From this anthropometric data and the high resolution scan of the kneejoint 70, the femoral mechanical axis FM and tibial mechanical axis TMcan be determined, at 1106, and located in a two- or three-dimensionalimage model of the knee joint 70 as reconstructed from the knee jointscan, at 1108. Based on the image model, a pre-operative plan can beprepared, at 1110, as discussed above. Patient-specific alignmentguides, other associated instruments and/or patient-specific,semi-custom, or non-custom implants can be made based on thepre-operative plan and the determination of the mechanical axis of thepatient. The patient-specific alignment guides can include, for example,a three-dimensional bone engagement surface which is designed to be mateand be complementary to the three-dimensional surface of the image modelof the knee joint, as discussed in detail in the patent applicationscross-referenced above and incorporated herein by reference.

Referring to FIGS. 19 and 20, instead of using anthropometric data, adigital photographic image of the patient 60 in front of a grid surface1120 or other reference surface can obtained pre-operatively using adigital photographic equipment 1130, as illustrated in FIG. 19. Usingthe digital photographic image, the hip center 76, knee center 75 andankle center 78 can be identified on the grid surface 1120 and thecorresponding hip height H1, tibial height H2 and variousanatomic/mechanical axes (shown in FIG. 17) can be determined. It shouldbe appreciated that other methods of reference for the digitalphotographic image can be used, including, for example size- ororientation indicative markers on the patient or in reference to thepatient in the field of view of the camera.

Referring to flowchart of FIG. 20, a high resolution scan of the kneejoint 70 of the patient can be obtained pre-operatively at 1150. Adigital photographic image of the patient showing the leg anatomy infront of the grid surface 1120 is obtained, at 1152. The hip center 76and ankle center 78 can be determined from the digital image, at 1154.The femoral mechanical axis FM and tibial mechanical axis TM can also bedetermined from the digital image, at 1156. Using this information andthe using the high-resolution scan, a two-dimensional or athree-dimensional image model of the knee joint 70 showing the femoraland tibial mechanical axes FM and TM can be prepared at 1158. Based onthe image model, a pre-operative plan can be prepared, at 1160, asdiscussed above. Patient-specific alignment guides, other associatedinstruments and/or patient-specific, semi-custom, or non-custom implantscan be made based on the pre-operative plan and the determination of themechanical axis.

Referring to FIGS. 21, 22A and 22B, an image-free method of representinga specific patient's anatomy for pre-operative planning is illustrated.A database that includes images and measurements of diseased/deformedbones and bone joints can be created from in-house patient data or otherpublicly available data, at 1170. Personal patient data can also beobtained preoperatively, at 1172. The personal patient data can include,for example, height, weight, body mass index (BMI), age, gender, race,ethnicity, daily activity, disability, etc. A best-fir bone model,illustrated at FIG. 22A, can be selected from the database based on thepatient's personal data, at 1174. Optimization or iteration or visualselection can be used to select the best-fit bone model for the specificpatient. The best-fit bone model may still have parameters that differfrom the patient's personal data. After matching a patient with abest-fit bone model from the database that corresponds to one or more ofgender, age, disability, race, etc, some other personal parameters maynot quite match. For example, one or more of the hip height H1 or thetibial height H2, or the hip ankle α, or the tibial angle α may differfrom corresponding known values H1′, H2′, α′ and β′ of the patient thatare obtained pre-operatively for the specific patient, as discussedabove. A transformation program/software can be used to transform,deform or morph the best-fit bone model of FIG. 22A to a patientcustomized model shown in FIG. 22B, in which all the known parameters ofthe patient are matched without altering other details of the best-fitbone model of FIG. 22A, at 1176. Various commercially available softwareprograms can be used for the bone transformation/morphing, includingthose disclosed in U.S. Patent Application Publication 2004/006818,which is incorporated herein by reference. Based on the customizedmodel, a pre-operative plan can be prepared, at 1178, as discussedabove, and customized alignment guides, other associated instruments,and custom, semi-custom or non-custom implants can be made based on thepreoperative plan.

The methods described above in reference with FIGS. 16-22B, providedifferent choices for controlling the extent of pre-operative imagescanning of the patient for use in the pre-operative plan. The methodscan be used to prepare corresponding patient-specific orpatient-customized alignment guides and select implants, includingpatient-specific or customized implants, or semi-custom implants or noncustom, off-the-shelf implants, as discussed above.

The foregoing discussion discloses and describes merely exemplaryarrangements of the present teachings. Furthermore, the mixing andmatching of features, elements and/or functions between variousembodiments is expressly contemplated herein, so that one of ordinaryskill in the art would appreciate from this disclosure that features,elements and/or functions of one embodiment may be incorporated intoanother embodiment as appropriate, unless described otherwise above.Moreover, many modifications may be made to adapt a particular situationor material to the teachings of the invention without departing from theessential scope thereof. One skilled in the art will readily recognizefrom such discussion, and from the accompanying drawings and claims,that various changes, modifications and variations can be made thereinwithout departing from the spirit and scope of the present teachings asdefined in the following claims.

What is claimed is:
 1. A method for pre-operative orthopedic planningcomprising: obtaining only a high-resolution knee-joint scan of apatient; determining hip rotation center and ankle rotation center fromanthropometric data based on personal data of the patient; determining amechanical axis of the knee joint based on the anthropometric data;preparing at least a two-dimensional image model of the knee joint usingthe knee-joint scan and the determined mechanical axis; and preparing apre-operative surgical plan based on the image of the knee joint.
 2. Themethod of claim 1, wherein the high-resolution scan is one of MagneticResonance Imaging or Computer Tomography scan.
 3. The method of claim 1,wherein the personal data include a height of the patient.
 4. The methodof claim 2, wherein the personal data include gender, age and weight ofthe patient.
 5. The method of claim 1, wherein preparing a pre-operativesurgical plan further comprises preparing a patient-specific alignmentguide.
 6. The method of claim 5, wherein preparing a pre-operativesurgical plan further comprises selecting an implant for the patient. 7.The method of claim 6, wherein the implant is patient-specific.
 8. Themethod of claim 1, wherein preparing at least a two-dimensional imagemodel of the knee joint includes preparing a three-dimensional imagemodel of the knee joint.
 9. A method for pre-operative orthopedicplanning comprising: obtaining only a high-resolution knee-joint scan ofa patient; taking a digital photographic image of the patient;determining a hip rotation center and an ankle rotation center from thedigital photographic image; determining a mechanical axis of the kneejoint based on the knee-joint scan and the hip rotation center and anklerotation center; preparing an at least two-dimensional image model ofthe knee joint using the knee-joint scan and the determined mechanicalaxis; and preparing a pre-operative surgical plan based on the imagemodel of the knee joint.
 10. The method of claim 9, wherein preparing apre-operative surgical plan further comprises preparing apatient-specific alignment guide.
 11. The method of claim 10, whereinpreparing a pre-operative surgical plan further comprises selecting animplant for the patient.
 12. The method of claim 11, wherein the implantis patient-specific.
 13. The method of claim 9, wherein the digitalimage of the patient is taken against a grid surface.
 14. A method forpre-operative orthopedic planning comprising: creating a diseased bonedatabase; obtaining personal data of a patient; selecting a best-fitbone model from the diseased bone database based on the personal data ofthe patient; transforming the best fit model to a customized modelmatching the personal data of the patient; and preparing a pre-operativesurgical plan based on the customized model without obtaining image dataof the patient.
 15. The method of claim 14, wherein obtaining personaldata of a patient includes obtaining age, gender, weight and height ofthe patient.
 16. The method of claim 15, wherein transforming the bestfit model to a customized model matching the personal data of thepatient includes transforming the best-fit model to match a hip heightof the patient.
 17. The method of claim 15, wherein transforming thebest fit model to a model matching the personal data of the patientincludes transforming the best-fit model to match a tibial height of thepatient.
 18. The method of claim 15, wherein transforming the best fitmodel to a model matching the personal data of the patient includestransforming the best-fit model to match a hip angle of the patient. 19.The method of claim 15, wherein transforming the best fit model to amodel matching the personal data of the patient includes transformingthe best-fit model to match a tibial angle of the patient.
 20. Themethod of claim 14, wherein preparing a pre-operative surgical planfurther comprises preparing a customized alignment guide based on thecustomized model.